Article destroying devices are known. One type of article destroying device is a shredder. It is known that a shredder may jam.
One of the causes for service to certain shredder models is repeat jams. A jam condition disrupts project flow when an article fed into a shredder device wedges tightly between at least one moving component and a second component of the system, thus causing the moving component to lock into an unworkable state. The occurrence of a jam condition is in most instances caused by a media sheet or a stack of media sheets having a thickness that exceeds a maximum capacity of which the shredder can handle. Generally, the mechanical systems, such as, for example, a motor, gears, and rotating cylinders, are capable of handling media thicknesses within certain ranges. Stack thicknesses are tested as they relate to the number of Amps drawn on the motor. Excessive loading results when thicknesses draw an Amperage that causes the motor to stop working. In most instances, the motor needs a period of relief before the shredder device can complete the project.
There are known shredders that disable mechanical systems when stack thicknesses are in excess of a predetermined capacity. One known method utilized in a known shredder includes utilizing a mechanical switch that is moved from a first position to a second position when overly thick media pushes against a lever connected thereto. More specifically, an opposite portion of this lever is situated in a path generally in proximity to an entrance of the throat. Another method includes disabling the mechanical systems when the media comes within close proximity to a sensor that reads the conductivity of the media. This sensor is similarly situated in proximity of the throat and, more specifically, on an exterior of the shredder housing.
There are no known shredder systems that utilize a corresponding focus beam generator and receiver type sensor system to suspend an operation of the mechanical systems when overly thick media is inserted into the throat. Rather, known shredder devices generally incorporate focus beam sensors to activate the motor when media is placed in proximity to the entrance of the throat, i.e., feed slot. More specifically, the sensor generates a beam that is directed toward or travels in proximity to the entrance of the throat. Media interrupts the beam as it moves into the throat, thus causing the mechanical systems to activate. One aspect associated with sensors including transmitter and/or receiver photodiodes situated in the feed slot is that the shredder will fault when dust collects on a face of the sensor. The sensors are generally exposed to dust circulating in an environment exterior to the sensor. This dust falls into the feed slot and settles on the sensor. If the sensor is not routinely cleaned, it will inaccurately conclude that media is inserted into the slot. The motor may continue to run when no media is present.
Utilization of a focus beam sensor is a reliable mechanism to detect specific conditions relating to the over-feeding of media into the feed throat of a destroying device. A thickness detection sensor that includes at least one of a transmitter and receiver is situated in a closed region away from the throat and the external environment.